1. Field of the Invention
The present invention relates to a top cover, a disk drive apparatus, and a method of manufacturing the top cover.
2. Description of the Related Art
A disk drive apparatus, such as a hard disk apparatus or an optical disk apparatus, typically includes a gasket between a base plate and a top cover in order to maintain hermetic sealing of an interior thereof.
JP-A 2001-311470, for example, describes a known hard disk apparatus including such a gasket. In the hard disk apparatus described in JP-A 2001-311470, a top cover and a cover gasket are fixed to each other through an adhesive (see, for example, claim 1 and paragraph [0028] of JP-A 2001-311470).
However, when the adhesive is used to fix the cover gasket to the top cover as in the hard disk apparatus described in JP-A 2001-311470, outgassing from the adhesive may occur. The outgassing from the adhesive may occur, not only when the adhesive is cured, but also even after the hard disk apparatus or the like is assembled. Then, if minute particles in a gas resulting from the outgassing from the adhesive are adhered to a disk, an error may occur in reading or writing from or to the disk.
Meanwhile, in recent years, capacities of disks used in disk drive apparatuses have been increasing, and there has accordingly been a technical demand for increased cleanliness in the disk drive apparatuses. For example, there has been a demand to reduce outgassing in the disk drive apparatuses. However, when the adhesive is used to fix the cover gasket to the top cover as in the hard disk apparatus described in JP-A 2001-311470, it is difficult to reduce the outgassing.